Jak-STAT signaling pathway Rapid signaling pathway by which some
extracellular signals (for example interferon) activate gene expression.
Involves cell-surface receptors and cytoplasmic Janus kinases (Jaks) plus
signal transducers and activators of transcription (STATs).

joule Standard unit of energy in the meter-kilogram system. One joule is the
energy delivered in one second by a one-watt power source. Approximately
equal to 0.24 calories.